Daily Tasks and Willingness to Work of Dental Hygienists in Nursing Facilities Using Japanese Dental Hygienists' Survey 2019.

Oral health care by dental hygienists contributes to the maintenance of nutritional and general health for older people in nursing facilities. This study aimed to investigate daily tasks and willingness to work among dental hygienists working in nursing facilities in Japan. In 2019, using a self-administered questionnaire, a postal cross-sectional survey was conducted among members of the Japanese Dental Hygienists' Association. Questionnaires were distributed to all 16,722 Association members (responses, n = 8932; return rate, 53.4%). We analysed data from 368 dental hygienists currently working in nursing facilities. Item response theory and correspondence analyses were performed. In total, >90% of dental hygienists undertook oral examinations and provided oral hygiene instructions to residents and facility staff. In contrast, the implementation rate of tasks related to interprofessional collaboration was relatively low (approximately 50%), and 72.6% of dental hygienists indicated that they wanted to continue working in nursing facilities. Their willingness to work was closely associated with work involving interprofessional collaboration. Our study findings showed that dental hygienists' work content in nursing facilities was diverse, but that there was variation in implemented tasks. Willingness to continue working in nursing facilities was associated with interprofessional collaboration among dental hygienists.

Impact of Working Environment on Job Satisfaction: Findings from a Survey of Japanese Dental Hygienists.

In Japan, there is currently a shortage of dental hygienists. The number of dental hygienists as a workforce at dental clinical practice is not sufficient. Several factors affect career retention and job satisfaction of hygienists and these factors are considered to correlate with each other to construct networks. The aim of this study was to present a structural model of job satisfaction of Japanese dental hygienists and to determine the characteristics of unmotivated hygienists. The Japan Dental Hygienists' Association has conducted a survey on their working environments every five years since 1981. Questionnaires were sent to all members of the association (16,113) and 8932 answers were returned. The data of 3807 active dental hygienists who worked at clinics were analyzed. Items associated with job satisfaction were derived from two latent variables, namely, the intrinsic psychosocial factors for the value of the work and extrinsic employment advantage. Based on the structural equation modeling, the association of value was higher than that of advantage. Most of the hygienists wished to continue working as dental hygienists. More than 60% felt their work required a high level of expertise. The value of the profession is deeply rooted in job satisfaction, motivation, and job retention of Japanese dental hygienists. Working environments where dental hygienists make great use of their specialized skills can lead to high career retention which prevent them from taking career breaks.

Factors Affecting the Reinstatement of the Japanese Dental Hygienist: A Japanese Dental Hygienist Survey Conducted in 2019.

There is a shortage of dental hygienists for dental clinics in Japan. An ideal solution would be for dormant dental hygienists to re-enter the workforce. In this study, we identified the obstacles preventing these dental hygienists from re-entering the workforce. The Japan Dental Hygienists' Association surveyed all 16,113 members about their working conditions. Among the 101 items in the questionnaire, 11 items specifically targeted the reasons why dental hygienists leave their jobs. Among 8780 responses (54.5%), 1063 were from members who had resigned from jobs as dental hygienists. Three hundred and fifty-five (34.4%) answered "Yes" to the question "I would like to return to work if conditions are satisfactory." The most frequent cause for leaving a job was" Childbirth and child-rearing" (16.9%). "Working status/working hours" (15.7%) was the main obstacle to re-entry. Furthermore, dental hygienists with intentions to re-enter decided to leave their jobs most frequently because of "Childbirth and child-rearing" and "Working status/working hours." Improvement of the social support system for dental hygienists is required to ensure a sufficient supply of dental health services.

Improvement of the Working Environment and Daily Work-Related Tasks of Dental Hygienists Working in Private Dental Offices from the Japan Dental Hygienists' Association Survey 2019.

A dental hygienist performs various daily work-related tasks. The aim of this study was to elucidate the daily work-related tasks of Japanese dental hygienists and construct groups to understand the relationships between daily work-related tasks, the attractiveness of dental hygienist work, and the improvement of the working environment. The Japan Dental Hygienists' Association has conducted a postal survey on the employment status of dental hygienists in Japan every five years since 1981. The data on the implementation of 74 daily work-related tasks in dental offices were analyzed from the survey carried out in 2019. The questionnaires were distributed to 16,722 dental hygienists and 8932 were returned (collection rate: 53.4%). The 3796 dental hygienists working at dental clinics were clearly classified into nine groups. Full-time workers requested a reduced workload. Part-time workers requested better treatment rather than reducing the workload. Salary and human relationships were common problems with the working environment. Full-time workers felt that job security was an attractive feature of the dental hygienist role. The data presented in this study may help with the improvement of working conditions for dental hygienists.

Improvement of Workplace Environment That Affects Motivation of Japanese Dental Hygienists.

Dental hygienists are in high demand due to insufficient workforce and a lack of an effective reinstatement support system. We investigated the reasons for willingness to work by analyzing the survey results of the employment status of Japanese dental hygienists conducted by Japan Dental Hygienists' Association. In total, we mailed 16,113 questionnaires to all members of the association (response rate 53.4%). We carried out statistical analysis to determine the specific items to improve the hygienists' working environment. Fourteen factors of working conditions that they wish to improve were determined. Structural equation modeling showed that a path, "Reduction of work volume", "Reduction of working hours" and "Increased number of holidays" were higher than other items. A decision analysis demonstrated that most of the respondents answered "Yes" to "Improvement in working conditions including higher salary" out of those who answered, "Strongly disagree" for "Do you feel that dental hygienist work is rewarding?". Improving workplace environment is integral to keeping high levels of work motivation and a low turnover rate. Most of the hygienists wish for a salary raise among all the conditions. The transition from conventional work styles to non-conventional flexible working patterns is needed.

Job Attractiveness and Job Satisfaction of Dental Hygienists: From Japanese Dental Hygienists' Survey 2019.

Job attractiveness and job satisfaction are important factors in the continuity of employment among healthcare professionals. The aim of this study was to assess job satisfaction and job attractiveness among dental hygienists in Japan. The Japan Dental Hygienists Association conducted a survey of the employment status of Japanese dental hygienists in 2019. Questionnaires were distributed to all 16,722 members, and 8932 were returned (Collection rate: 53.4%). Data from 7869 currently working dental hygienists were analysed in this study. We analysed seven items of job attractiveness, 14 items of job satisfaction, and 13 items of request for improving the working environment. Item response theory and structural equation modelling (SEM) were utilized for the analysis. For attractiveness of dental hygienists' work, respondents placed greater emphasis on the fact that dental hygienists needed national qualifications rather than on income stability. SEM showed that job satisfaction consisted of two factors, 'Value for work' and 'Working environment', as did job attractiveness, with 'Contribution' and 'Assured income'. Value for work affects the contribution to people, and, employment environment affects assured income. Improving job satisfaction and work environments could help to improve the employment rate of dental hygienists, which could positively influence patient care.

Development of Innovative Contra-angle Handpiece Device with Piston Movement for Root Canal Preparation.

INTRODUCTION: The purpose of this study was to assess the optimal amplitude and weight of the newly developed contra-angle handpiece. The handpiece uses piston movement without using an endodontic motor and enables a safe, quick, and reliable canal preparation. METHODS: A prototype handpiece was designed. Instrumentation was performed on root canal resin blocks by 20 operators in 3 groups: the prototype handpiece with an H file (a stainless steel #25 manual H file, the piston group), a manually standardized technique with a K file (stainless steel #15-25 K files, the manual group), and a nickel-titanium (NiTi) reciprocating file with an endodontic motor (Reciproc Blue R25 [VDW, Munich, Germany], the NiTi group). Transportation of the canal center line and the time required for preparation were measured and statistically analyzed. RESULTS: The optimal condition was an amplitude of 1.35 mm and a weight of 61.0 g. Transportation of the canal center was observed in all groups. A statistically significant difference was found at 2.0-3.0 mm from the apical foramen between the piston or NiTi group and the manual group, but no significant difference was found between the piston and NiTi groups. The least transportation was found in the NiTi and piston groups. The handpiece with a #25 H file demonstrated a good centering ability, similar to the NiTi file, which enabled speedy preparation. The time required for preparation between the piston or NiTi group and the manual group was statistically different. No significant difference was observed between the piston and NiTi groups (P < .05). CONCLUSIONS: We concluded that the newly designed handpiece achieved efficient canal preparation and negotiation. The handpiece could avoid endodontic accidents, including ledge formation, instrument separation, and perforation.

Dental Hygienists' Practice in Perioperative Oral Care Management According to the Japanese Dental Hygienists Survey 2019.

Perioperative oral care management is effective in the prevention of postoperative complications, and dental hygienists play an important role. The aim of this study was to elucidate the practice and substantial role of dental hygienists in perioperative oral care management. The Japan Dental Hygienists Association conducted a survey of the employment status of Japanese dental hygienists in 2019. Questionnaires were distributed to all 16,722 members, and 8932 were returned (collection rate: 53.4%). A total of 3560 dental hygienists were working at dental clinics and 1450 (38.2%) were performing perioperative oral care management. More than 90% of them implemented conventional oral care practice. Less than half of the dental hygienists implemented treatment concerning oral functions. Only 9.9% of dental hygienists recognized shortened hospital stay as an effect of perioperative oral care management. Dental hygienists who implemented both nutritional instruction and training of swallowing function or mouth rinsing instructions recognized the shortened hospital stay effect. Overall implementation of perioperative oral care management led to shortened hospital stay. Implementation of perioperative oral care management required knowledge and skills related to systemic health conditions. A stepwise educational program is necessary for perioperative oral care management to become commonplace for dental hygienists.

Characterization of Living Dental Pulp Cells in Direct Contact with Mineral Trioxide Aggregate.

Mineral trioxide aggregate (MTA) was introduced as a material for dental endodontic regenerative therapy. Here, we show the dynamics of living dental pulp cells in direct contact with an MTA disk. A red fluorescence protein (DsRed) was introduced into immortalized porcine dental pulp cells (PPU7) and cloned. DsRed-PPU7 cells were cultured on the MTA disk and cell proliferation, chemotaxis, the effects of growth factors and the gene expression of cells were investigated at the biological, histomorphological and genetic cell levels. Mineralized precipitates formed in the DsRed-PPU7 cells were characterized with crystal structural analysis. DsRed-PPU7 cells proliferated in the central part of the MTA disk until Day 6 and displayed a tendency to move to the outer circumference. Both transforming growth factor beta and bone morphogenetic protein promoted the proliferation and movement of DsRed-PPU7 cells and also enhanced the expression levels of odontoblastic gene differentiation markers. Mineralized precipitates formed in DsRed-PPU7 were composed of calcium and phosphate but its crystals were different in each position. Our investigation showed that DsRed-PPU7 cells in direct contact with the MTA disk could differentiate into odontoblasts by controlling cell-cell and cell-substrate interactions depending on cell adhesion and the surrounding environment of the MTA.

Prioritization of the Skills to Be Mastered for the Daily Jobs of Japanese Dental Hygienists.

Dental hygienists require proficiency in a wide variety of job skills. Dental hygienists should master their job skills step by step, and the prioritization of these steps is important. In this study, we investigated the frequency at which Japanese dental hygienists performed daily jobs and attempted to classify the jobs according to the proficiency levels. The aim of this study was to surmise the order in which skills should be mastered in terms of priority and to investigate the relationship between daily jobs and the motivation for completing jobs. The Japan Dental Hygienists' Association conducts a survey on the employment status of dental hygienists in Japan every five years. The questionnaire is distributed to all members of the Japan Dental Hygienists' Association. In this study, the responses of 3,807 dental hygienists who worked at dental clinics were analyzed. We analyzed 77 kinds of daily jobs and the items regarding the motivation to work. For the analysis, item response theory (IRT), structural equation modeling (SEM), and logistic regression analysis were applied. According to the item response curve, the jobs were classified into 11 clusters. The jobs classified into Cluster 1 were the jobs that most of the average-proficiency Japanese dental hygienists performed. Scaling and root planing were the representative jobs in Cluster 1. Performing the jobs classified into Cluster 5 clearly discriminated whether the dental hygienists were performing multiple jobs. Jobs concerning care for elderly or disabled patients were classified into Cluster 5. Jobs concerning gerodontology, implants, management of staff, and consultations were significantly associated with the motivation to perform jobs. Polishing and adjustment of orthodontic apparatuses was negatively associated with the motivation to perform jobs. Understanding the features of each daily job of dental hygienists is important for planning dental hygienists' lifelong educational programs and evaluating their skill levels and proficiency levels. The results presented in this study may help to reveal the characteristics of dental hygienists' daily jobs.

[Efficacy of Slightly Acidic Electrolyzed Water against Contamination of Water Line of Dental Units].

OBJECTIVES: The purpose of this study was to evaluate the efficacy of slightly acidic electrolyzed water (SAEW) against the contamination of the water line of dental units and the effects of SAEW on the water line. MATERIALS AND METHODS: The experimental material was a prototype dental unit equipped with a SAEW generator. SAEW is directly supplied to each device or part of this unit system. Experimental SAEW samples were collected from a high-speed handpiece (HS-1), an ultrasonic scaler, and a cup filler of the prototype dental unit. Control samples were taken before and after the prescribed flushing from another high-speed handpiece (HS-2) that is directly supplied with tap water in the same dental unit. The samples were analyzed for free chlorine and heterotrophic bacteria for 7 years to assess the efficacy and effects of SAEW. The substances eluted in SAEW were examined to investigate the effect of SAEW on the water line. A questionnaire survey was conducted on patients on whom dental uints supplied with SAEW were used. RESULTS: SAEW always showed a higher free chlorine concentration than tap water during the observation period of 7 years. In HS-2 supplied with tap water, the free chlorine concentration increased significantly owing to the prescribed flushing. SAEW always showed a significantly smaller number of heterotrophic bacteria than tap water. No abnormal levels values of water line components eluted into SAEW were observed. There were few negative comments from patients on whom dental units supplied with SAEW were used. CONCLUSIONS: SAEW continuously used for 7 years was effective for contamination control in the water line of dental units.

A review of the literature on the efficacy of mineral trioxide aggregate in conservative dentistry.

The aim of this literature review was to assess the clinical performance of MTA to establish the evidence level for its effectiveness in vital pulp therapy, perforation repair, and retrograde root canal filling. A comprehensive literature survey was performed via electronic databases of PubMed/MEDLINE. A total of 58 papers were reviewed in this study, of which 2 were systematic reviews/meta-analysis, 9 were randomized controlled trials (RCTs), and the rest were fallen into other categories. Mineral trioxide aggregate (MTA) provided better pulp protection as a direct capping material when compared with calcium hydroxide. As perforation repair materials, MTA demonstrated an excellent sealing ability in vitro. For periodontal tissues around a perforation, MTA provided normal healing processes in clinical trials. It is therefore concluded that MTA has a high potential in repairing perforations. MTA is the most promising material when used for retrograde root canal filling demonstrating normal healing in short/long term clinical outcomes.

Effects of Er:YAG and Diode Laser Irradiation on Dental Pulp Cells and Tissues.

Vital pulp therapy (VPT) is to preserve the nerve and maintain healthy dental pulp tissue. Laser irradiation (LI) is beneficial for VPT. Understanding how LI affects dental pulp cells and tissues is necessary to elucidate the mechanism of reparative dentin and dentin regeneration. Here, we show how Er:YAG-LI and diode-LI modulated cell proliferation, apoptosis, gene expression, protease activation, and mineralization induction in dental pulp cells and tissues using cell culture, immunohistochemical, genetic, and protein analysis techniques. Both LIs promoted proliferation in porcine dental pulp-derived cell lines (PPU-7), although the cell growth rate between the LIs was different. In addition to proliferation, both LIs also caused apoptosis; however, the apoptotic index for Er:YAG-LI was higher than that for diode-LI. The mRNA level of odontoblastic gene markers-two dentin sialophosphoprotein splicing variants and matrix metalloprotease (MMP)20 were enhanced by diode-LI, whereas MMP2 was increased by Er:YAG-LI. Both LIs enhanced alkaline phosphatase activity, suggesting that they may help induce PPU-7 differentiation into odontoblast-like cells. In terms of mineralization induction, the LIs were not significantly different, although their cell reactivity was likely different. Both LIs activated four MMPs in porcine dental pulp tissues. We helped elucidate how reparative dentin is formed during laser treatments.

Bone Response to Titanium Implants Coated with Double- or Single-Stranded DNA.

We aimed to evaluate in vivo bone response and in vitro apatite formation to titanium (Ti) implants, coated with double-stranded DNA (DNA-d) or single-stranded DNA (DNA-s), and to compare the influence in different structure of DNA, double strand and single strand on bone response and apatite formation. The bone responses to multilayered DNA-d/protamine or DNA-s/protamine coating implants were evaluated after implantation into the extracted sockets of rat maxillary molars. Apatite formation on either coating surface after immersion in simulated body fluid (SBF) was evaluated using the quartz crystal microbalance (QCM) method. DNA-d/protamine and DNA-s/protamine coatings produced more roughened and hydrophilic surfaces than untreated Ti. Animal experiments showed that higher bone-to-implant ratios were achieved 3 and 6 weeks after implantation using DNA-d/protamine and DNA-s/protamine coatings compared with Ti. QCM measurements revealed that each coating contributed to significant earlier apatite formation in SBF. We conclude that both DNA-d/protamine and DNA-s/protamine coatings enhanced early bone formation. We suggest that a DNA-multilayer coating is useful for the surface modification of a Ti implant.

A case of tooth fracture occurred upon medicating bisphosphonate for an elderly person: Preservation therapy and responses for Stage 0 of bisphosphonate-related osteonecrosis of jaw.

This case report aimed to report the progress of preservation therapy and response of symptoms and signs for Stage 0 of bisphosphonate-related osteonecrosis of jaw (BRONJ). A 68-year-old female was recognized having a tooth at the left upper first molar fracture upon medicating bisphosphonate (BP) in 2007. At that time, the extraction of the tooth was an absolute contraindication. Therefore, we performed preservation therapy. We observed the symptoms and signs every month. After 5 months, swelling and redness in the entire first molar tooth were seen and fistula formed partly. Bone exposure was not seen. We administrated antibiotics immediately. As a result, symptoms disappeared. On April 10, 2009, the patient visited us as she felt a sense of incongruity in the lower left first and second molar teeth. Clinically, there were no symptoms of pain. However, we observed the radiolucent finding in about 5 mm diameter at apical position by X-ray photography; we considered a possibility of Stage 0 for BRONJ. We immediately administered medicine for 5 days and the symptoms disappeared. At present, no inflammation with signs and symptoms at the upper left first molar and lower left first, second molar parts is shown. We performed preservation therapy for tooth fracture case medicating of BP. Immediate responses for inflammation and symptoms of the Stage 0 of BRONJ have led to success. Hence, dentists should perform regular clinical observation, and enough education to the patient for BRONJ is necessary.

Enamel surface changes caused by hydrogen sulfide.

BACKGROUND: Volatile sulfur compounds (VSCs) produced inside the mouth are a well-known cause of halitosis. Recent studies have suggested that VSCs modify the pathology of periodontitis by encouraging the migration of bacterial toxins associated with increased permeability of gingival epithelia, and enhancing the production of matrix metalloproteinases in gingival connective tissue. Nonetheless, the effects on the enamel of direct exposure to VSCs within the oral cavity remain unclear. In the present study, we observed the effects of VSCs in the form of hydrogen sulfide (H2S) on enamel surfaces and determined their effects on restorations. MATERIALS AND METHODS: Extracted human tooth and bovine tooth samples were divided into the H2S experimental side and the control side. We observed the effects of H2S on enamel surfaces using electron microscopy and conducted a shear test. RESULTS: We found that exposure to H2S obscured the enamel surface's crystal structure. The surface also exhibited coarseness and reticular changes. Shear testing did not reveal any differences in bond strength. CONCLUSIONS: Our findings suggested that H2S occurring inside the mouth causes changes to the crystal structure of the enamel surface that can lead to tooth wear, but that it does not diminish the effects of dental bonding in adhesive restorations.

Detection of a secondary mesio-buccal canal in maxillary first molar: A comparative study.

AIM: The purpose of this study was to clarify detection characteristics of the secondary mesio-buccal canal in maxillary first molars using various methods. MATERIALS AND METHODS: The root canal system of 86 extracted human maxillary first molars was inspected using micro-focus-computed tomography to accurately determine the number of canals. Radiographs or floors of the pulp chamber for all samples were observed for the secondary mesio-buccal canal with computed tomography for dentistry, digital dental radiography, magnifier, or the naked eye. Sensitivity, specificity, positive, and negative predictive values and diagnostic accuracy for these four methods were investigated using the results from the micro-focus-computed tomography inspection as the gold standard. All samples of each method were observed by 10 endodontists. Using these results, the χ(2) test was used to compare and analyze differences between the various conditions (P<0.05). RESULTS: The secondary mesio-buccal canal could be recognized in 60.9% of samples with the micro-focus-computed tomography. No significant difference was seen between efficiencies of the computed tomography for dentistry and the micro-focus-computed tomography. The computed tomography for dentistry was superior to the other three methods. CONCLUSION: Detectability of the secondary mesio-buccal canal in the maxillary first molar was superior using dental-computed tomography compared to digital dental radiography, magnification telescope, and the naked eye.

Generation of gaseous sulfur-containing compounds in tumour tissue and suppression of gas diffusion as an antitumour treatment.

BACKGROUND AND AIMS: The mechanisms of cancer cell growth and metastasis are still not entirely understood, especially from the viewpoint of chemical reactions in tumours. Glycolytic metabolism is markedly accelerated in cancer cells, causing the accumulation of glucose (a reducing sugar) and methionine (an amino acid), which can non-enzymatically react and form carcinogenic substances. There is speculation that this reaction produces gaseous sulfur-containing compounds in tumour tissue. The aims of this study were to clarify the products in tumour and to investigate their effect on tumour proliferation. METHODS: Products formed in the reaction between glucose and methionine or its metabolites were analysed in vitro using gas chromatography. Flatus samples from patients with colon cancer and exhaled air samples from patients with lung cancer were analysed using near-edge x-ray fine adsorption structure spectroscopy and compared with those from healthy individuals. The tumour proliferation rates of mice into which HT29 human colon cancer cells had been implanted were compared with those of mice in which the cancer cells were surrounded by sodium hyaluronate gel to prevent diffusion of gaseous material into the healthy cells. RESULTS: Gaseous sulfur-containing compounds such as methanethiol and hydrogen sulfide were produced when glucose was allowed to react with methionine or its metabolites homocysteine or cysteine. Near-edge x-ray fine adsorption structure spectroscopy showed that the concentrations of sulfur-containing compounds in the samples of flatus from patients with colon cancer and in the samples of exhaled air from patients with lung cancer were significantly higher than in those from healthy individuals. Animal experiments showed that preventing the diffusion of sulfur-containing compounds had a pronounced antitumour effect. CONCLUSIONS: Gaseous sulfur-containing compounds are the main products in tumours and preventing the diffusion of these compounds reduces the tumour proliferation rate, which suggests the possibility of a new approach to cancer treatment.

Application of thermography in dentistry--visualization of temperature distribution on oral tissues.

The purpose of this study was to devise and propose appropriate conditions for the photographing of thermal images in the oral cavity and to evaluate which thermography techniques can be applied to dentistry by evaluating the differences in temperature among oral tissues. Thermal images of oral cavities of 20 volunteers in normal oral condition were taken according to the guidelines of the Japanese Society of Thermography, with five added items for oral observation. The use of a mirror made it possible to take thermal images of the posterior portion or palate. Teeth, free gingiva, attached gingiva and alveolar mucosa were identified on thermal images. There were differences in temperature between teeth, free gingiva, attached gingiva and alveolar mucosa. These were nearly in agreement with the anatomical view. Thermography need no longer be restricted to the anterior portion using a mirror, and can now be applied to the dental region.